Stave-press.



No. 733,357. PATENTED JULY 7, 1903. A. HOPPMANN.

STAVE PRESS.

APPLIOATIOH FILED FEB. 4, 1903.

N0 MODEL. 2 SHEE 1.

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PATENTED JULY 7, 1903.

2 sums-sum 2.

A TTOHNE) A. HOFFMANN.

STAVE PRESS.

APPLICATION FILED FEB. 4. 19.03.

NO MODEL.

UNITED STATE Patented July 7, 1903.

PATENT OFFICE.

STAVE-PRESS.

SPECIFICATION forming part of Letters Patent No. 733,357, dated July 7, 1903.

Application filed February 4, 1903. Serial No. 141,822. (No model) I T (0% whom, it may concern:

Be it known that 1, AUGUST HOFFMANN, a citizen of the United States, residing at St. Louis, State of Missouri, have invented certain new and usefullmprovements in Stave- Presses, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

My invention has relation to improvements in stave-presses; and it consists in the novel construction of press more fully set forth in the specification and pointed out in the claims.

In the drawings, Figure 1 is a front elevation of the machine with the operating parts in their lowest position. Fig. 2 is a similar View with the parts in their elevated position. Fig. 3 is a vertical transverse section on line 3 3 of Fig. 2. Fig. 4 is a horizontal section on line 4 at of Fig. 1. Fig. 5 is a detached plan view of the stave holder or frame. Fig. 6 is a side elevation thereof. Fig. 7 is a transverse section on line 7 7 of Fig. 10, taken through one of the rocking platforms. Fig. Sis a top plan of the rocking platforms. Fig. 9 is an end view thereof. Fig. 10 is a longitudinal section on line 10 10 of Fig. 8. Fig. 11 is a detached view showing top plan of the die, and Fig. 12 is a vertical section on line 12 12of Fig. 11.

The object of my invention is to construct a stave-press which shall insure a uniform product in the bent stave, one which can operate on several staves at one time, thereby insuring a maximum capacity for the same, one which is simple, durable, and having a minimum number of operating parts, and one which possesses further and other advantages better apparent from a detailed description of the invention, which is as follows:

Referring to the drawings, 1 represents a suitable machine-frame, the same having disposed along the lateral vertical members thereof guide-blocks 2 for the cross-head 3. To the middle of the latter is pivoted one end of a connecting-rod composed of two right and left hand screw-threaded sections 4 4, respectively, connected by a nut 5 for adjusting the length of the said rod, the opposite end of the connecting-rod being pivotallysecured to a crank-arm 6, carried by the shaft 7 at the upper end of the frame. The for ward end of the shaft has secured thereto a worm-wheel 8, with which meshes a wormpinion 9 on the main drive-shaft 10, the latter carrying a pulley 11, from which leads a belt 11 to any suitable source of power. (Not shown.) Mounted on the shaft 10 exteriorly to the frame 1 is a bevel-gear 12, meshing with a similar gear 13 at the upper end of the vertical shaft 14, the lower end of the latter carrying a second gear-wheel 15, which engages a similar bevel-gear 16 at the adjacent end of a lower worm-shaft 17, disposed parallel to the shaft 10. The worm 18 on said lower shaft meshes with a worm-wheel19, located below and in the plane of the wheel 8, the shaft 20 of said wheel 19 being provided with a crank-arm 21, to which is coupled a similar connecting-rod 4 4. upper end of the connecting-rod 4c 4 passes a bar 22, whose free ends are guided in the reciprocations of the bar in the verticallyslottecl bearings or standards 23, suitable washers 24 retaining the bar against displacement.

Disposed in suitable bearings 24., carried by the lower parallel beams 25 of the frame, are transverse shafts 26 26, about which are adapted to oscillate the rocking platforms or rockers 27 27, the former being provided with bifurcated arms 28, which embrace the adjacent tongue 29 of the rocker 27, Figs. 8, 10, the tongue 29 being channeled out longitudinally and its terminal walls being likewise bifurcated, the channel of said tongue allowing for the free passage therethrough of the bar 22 and the bifurcations fully embracing said bar and overlapping one another, so as to form an inclosing opening or passage 30, Fig. 10, for said bar.

Motion being imparted to the drive-shaft, as indicated by the arrow, Fig. 1, the crosshead 3 and bar 22 will have a reciprocating motion imparted simultaneously thereto in the same direction, and as the cross-head rises the bar 22 will rise, the latter being depressed as the cross-head begins to descend. When the bar 22 rises, it rocks the platforms 27 27 upwardly, Fig. 2, and when it descends it draws them down after it, Fig. 1. Since the platforms are pivoted each to astationary rock-shaft, it follows that the adjacent forked ends of the rockers must neces- Through the sarily play or ride over the bar 22 in its reciprocations a distance substantially equal to the versed sine of the are described in the oscillations of the rockers. As the rockers approach a horizontal position the bar 22 will thus approach their respective axes of oscillation, and the adjacent ends of the rockers will thereby overlap the axis of the bar to a greater extent than is the case when the bar occupies either of its extreme positions. It follows from this that as the axis of the bar 22 approaches a point intermediate of its extreme positions from either end of its stroke the free adjacent ends of the rockers will follow or lag a little behind it, and thus allow the cross-head to slightly advance toward the rockers and reduce the distance or space which obtains between the cross-head and the ends of the rockers at the beginning of the respective strokes of the cross-head and bar. In other words, the inner oscillating ends of the rockers describe an arc while the bar 22 describes the sine of the arc while approaching the axes .of oscillation of the rockers, thus placing the point describing the are a little behind the point traversing the sine. Of course as the arc approaches the horizontal the sine and the are approximate each other as to length and the difference in speed disappears. The purpose of the cross-head in thus gaining on the rockers in each stroke will be presently apparent, since it explains the method by which the staves are subjected to compression and how they are released when once compressed. The overlapping ends of the rockers are protected by a straddle-plate 31, Fig. 8, riveted to rocker 27' and riding freely over rocker 27. The cross-head is pro vided with parallel grooves or ways 32 for the reception of the tongues 32 of the die 33, the tongues being loosely fitted in said grooves and the jar incident to compression of the staves being initially taken up by buffersprings 34, interposed between the upper surface of the die and the adjacent surface of the cross-head. The staves S are deposited in a holder or frame, Fig. 5, composed of terminal angle -bars 35, connected by lateral flexible straps 36, the inner face of one of the bars 35 being provided with ears or lugs 37, between which are pivoted the gravity-latches 38, made, preferably, of two sections united by a nut 39, whereby the length of the latch may be accurately adjusted. The free ends of the latches ride over tracks or ways 40, Fig. 6. The stock is deposited on the anglebars, Fig. 5, and the holder placed on top of the rockers 27 27, Fig. 2. When the staves are bent or pressed into the required shape, Fig. 1, an operation which serves to bring the angle-bars closer together, the hooked ends of the latches will ride over the ways 40 and finally drop and engage the catches 41 on the outside of the adjacent angle-bar and lock the holder against expansion, the bent staves being thus confined in the locked holder. To prevent spreading of the holder while the staves are subjected to compression, I provide the rockers with abutmentblocks 42, adjustably secured to the rockers by means of bolts 43, passed through slots 44 of the rockers, Fig. 10, the abutments being further reinforced by means of screws 45, hearing against the abutments, the screws being carried by extension-walls 46, formed with the rockers. To receive the main or body portions of the original stock or stave, I form a series of troughs or depressions 47 in the length of the rockers, such depressions being separated by grooves 48, running parallel thereto. To take up a portion of the strain incident to the compression, I place suitable buffer-springs 4C9 adjacent to the abutments, Fig. 10, the said springs being adjustable from the bottom of the rockers by means of screws 50.

Referring to Fig. 2, it is apparent that since the die and bar 22 travel at substantially the same speed and in the same direction the increment in the speed of the die and crosshead over the adjacent ends of the rockers by which the staves are carried is necessary to effect the compression of the stave, for were the actual speed the same the rockers would simply follow the die and cross-head in their reciprocations without gripping the staves; but, as explained above, the crosshead gains on the rockers, thereby diminishing the actual distance between them after a stroke is once started, the stave being thereby gripped and bent to the required curvature. In the ascending stroke the die and cross-head will gain slightly on the rockers, thereby permitting the operator to withdraw the locked holder with its staves and insert a fresh holder with new stock by the time the parts have completed their upward stroke.

' straps 36 are made of flexible malleable sheet metal, so that there is no danger of breaking by the constant bending and unbending of the stave-holder.

I do not, of course, wish to be limited to the details here shown, as these may in a measure be departed from without affecting the nature or spirit of my invention.

Having described my invention, what I claim is 1. In a stave-press, a pair of pivoted rockers hinged each to a stationary axis and having their free ends overlapping one another, a channel formed along the free or oscillating end of one of the rockers, a bar passed through said channel and loosely embraced by the free or oscillating end of the opposite rocker, slotted bearings for the ends of said bar, a connecting-rod coupled at one end to the bar, a crank-shaft coupled to the opposite end of the connecting-rod,a reciprocating die mounted in connection with the rockers, and inter* mediate gearing between the die and crankshaft coupled to the opposite end of the conshaft for imparting reciprocation to the die neoting rod, a reciprocating die mounted and bar, substantially as set forth. above the rockers, and intermediate gearing x5 2. In a stave-press, a pair of pivoted rookbetween the die and crank-shaft for impart- 5 ers, a channeled tongue having bifurcated 1 ing simultaneous reciprocation to the die and terminal Walls formed at the inner end of one bar, substantially as set forth.

rocker, bifurcated arms formed at the adja- In testimony whereof I affix my signature cent end of the opposite rocker and embracin presence of two witnesses. ing said tongue, a bar passed through the AUGUST HOFFMANN.

10 channel and respective bifurcations, slotted i Witnesses:

bearings for the ends of the bar, a connecti EMIL STAREK, in g-rod coupled at one end to the bar, a crankl G. L. BELFRY. 

